How does dexamethasone reduce cerebral edema?
As dexamethasone reduces edematous brain water content, the local tissue pressure is also reduced leading to an increase in peritumoral blood flow. This may be one of the mechanisms responsible for the increase in edematous brain perfusion seen in the current study.
How does DKA cause cerebral edema?
This occurrence is usually seen in newly diagnosed diabetic children with DKA. Cerebral edema occurs from rapid lowering of glucose levels and an ensuing rapid drop in plasma osmolarity. Brain cells, which trap osmotically active particles, preferentially absorb water and swell during rapid rehydration.
Why is cerebral edema a complication of DKA?
Cerebral edema is the leading cause of death in children presenting in diabetic ketoacidosis and occurs in 0.2 to 1% of cases. The osmolar gradient caused by the high blood glucose results in water shift from the intracelluar fluid (ICF) to the extracellular fluid (ECF) space and contraction of cell volume.
How does mannitol work in cerebral edema?
Mannitol is thought to decrease brain volume by decreasing overall water content, to reduce blood volume by vasoconstriction, to reduce CSF volume by decreasing water content. Mannitol may also improve cerebral perfusion by decreasing viscosity or altering red blood cell rheology.
What is the mechanism of action of corticosteroids?
Corticosteroids modify the functions of epidermal and dermal cells and of leukocytes participating in proliferative and inflammatory skin diseases. After passage through the cell membrane corticosteroids react with receptor proteins in the cytoplasm to form a steroid-receptor complex.
How does DKA prevent cerebral edema?
Therapeutic guidelines to prevent cerebral edema in diabetic ketoacidosis include slow rehydration over about 48 hours, avoidance of hypotonicity and of unnecessary alkali therapy. Early recognition of cerebral edema and prompt institution of hypertonic therapy with mannitol may prevent permanent neurological sequelae.
What is the pathophysiology of diabetic ketoacidosis?
Insulin deficiency, increased insulin counter-regulatory hormones (cortisol, glucagon, growth hormone, and catecholamines) and peripheral insulin resistance lead to hyperglycemia, dehydration, ketosis, and electrolyte imbalance which underlie the pathophysiology of DKA.
How do you treat cerebral edema in DKA?
Mannitol (0.25-1g/kg) is the most frequently used treatment for DKA-related cerebral edema. Mannitol should be given as soon as a clinical diagnosis of DKA-related cerebral edema is made.
How does dexamethasone work pharmacokinetics?
Corticosteroids bind to the glucocorticoid receptor, inhibiting pro-inflammatory signals, and promoting anti-inflammatory signals. Dexamethasone’s duration of action varies depending on the route.
